COVID-19 Mortality Is Attenuated at High Tropical and Subtropical Altitude: An Observational Study of a Database Covering Five Latin American Countries Less death from COVID-19 at high altitude

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Natalia Zubieta-DeUrioste Christian Arias-Reyes Lida Sanchez Nestor Freddy Armijo-Subieta Alfredo Merino-Luna Ivan Solarte Raffo Escalante-Kanashiro Jose Antonio Carmona-Suazo Enrique Maravi Poma Rosalinda Jimenez-Aguilar Jose M. Calle-Aracena Alberto Lopez-Bascope Roberto Vera Rafaela Zubieta-DeUrioste Ninoska Rossel Yeshua Peña-Y-Lilio Gary Chambi-Quilla Luis Herrera-Leon Santiago Garrido-Salazar Francisco Ney Villacorta Cordova Fausto Vinicio Maldonado Coronel Elisabeth Deindl Ricki Sheldon Roberto Alfonso Accinelli Edith M Schneider-Gasser Jorge Soliz Gustavo Zubieta-Calleja


The COVID-19 pandemic, caused by the SARS-COV-2 virus, has had devastating consequences worldwide. Remarkably, the incidence, virus transmission capacity, and severity of COVID-19 have been reported to be significantly decreased in high-altitude human populations. The clinical significance of these findings is enormous, as they suggest that permanent inhabitants of high altitudes have developed adaptive protective changes against certain pathologies. However, these observations have been overshadowed by contradictory reports on the COVID-19 mortality rate at high altitude, ascribed to low population densities. These interpretations, however, fail to consider that the environmental conditions of high-altitude regions of the temperate and tropical geographical zones are radically different from each other. Contrary to common thought, the conditions of high-altitude areas of countries within the tropical zone are so benign that they have favored the growth and development of densely populated cities. In this work, we use data from a COVID-19 database covering five Latin American countries in the tropical and subtropical geographic zone that corresponded to the period between the start of the pandemic and the end of 2020, when no vaccine was yet available. Our results reveal that residing above 1,000 m in tropical countries was a protective factor against COVID-19 mortality. Interestingly, this protective effect was independent of population size. The findings presented here, and those from other similar studies, substantiate the need for more research to reveal the secrets of the physiology of permanent high-altitude residents. In conclusion, our findings clearly demonstrate that the high-altitude environment in tropical and subtropical geographic zones significantly contributes to the decreased mortality impact of the SARS-COV-2 virus in high-altitude-exposed populations.

Keywords: SARS-CoV-2 first wave, ACE2, chronic hypobaric hypoxia, tolerance to hypoxia

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ZUBIETA-DEURIOSTE, Natalia et al. COVID-19 Mortality Is Attenuated at High Tropical and Subtropical Altitude: An Observational Study of a Database Covering Five Latin American Countries. Medical Research Archives, [S.l.], v. 11, n. 8, aug. 2023. ISSN 2375-1924. Available at: <>. Date accessed: 02 oct. 2023. doi:
Research Articles


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